Building Stones of Maryland

by Karen R. Kuff and James R. Brooks
1985

A building stone is defined as any massive, dense rock suitable for use
in construction. Whether igneous, metamorphic or sedimentary, a building
stone is chosen for its properties of durability, attractiveness, and economy.
A dimension stone is a building stone that is often quarried and prepared
in blocks according to specifications. A decorative stone is a stone that
can be quarried, cut or carved and is most highly valued for its pleasing
appearance. It is more often used in interior construction for decoration
and monuments than as standard building stone.

The Washington Monument, Baltimore, MD

There are a number of rocks in Maryland that have, at one time or another,
been used as building or decorative stone. The earliest settlers used local
fieldstone to build their houses. Later, as the demand grew for more elegant
buildings and monuments, stone was sought which was both durable, and attractive.
From the 1840's to the early 1900's, there were many quarries opened in Maryland
for the various types of building or decorative stones described herein.
The dimension, building, and decorative stone industries today are almost
non-existent because of competition from other, lower cost materials. Only
the Setters Quartzite, the Sykesville Gneiss, and some Paleozoic sandstones
are currently being quarried.

The first four "granites" and gneisses that are discussed were
frequently used in buildings around Baltimore. In descriptions of buildings,these
stones have often been confused, but with careful observation, the differences
between them can easily be noted.

Port Deposit "Granite"..... a coarse-grained, granite gneiss
with an obvious foliation produced by black mica. The rock was used in
early days by colonial settlers, but commercial use did not occur until
about 1816 when stone was needed for the abutments to the Susquehanna River
Bridge. A quarry was established at Port Deposit and by the 1830's much
of the stone was being shipped to Baltimore. Other quarries were opened
in Cecil County as the stone gained acceptance. Some of the buildings in
which this popular stone was used are: Fort Carroll, Fort McHenry, the
Naval Academy in Annapolis, Haverford College in Philadelphia, and part
of the old Goucher College in Baltimore. It is now quarried north of Havre
de Grace by the Arundel Corporation for use as crushed stone.

Baltimore Gneiss..... any of several similar looking banded gneisses
in a variety of colors, texture, and composition that were quarried along
the Jones Falls and Gwynns Falls in Baltimore City. It is thought that
the first buildings of Baltimore in the 1700's used stone quarried from
the Jones Falls gneiss, near the old Mount Royal railroad shops. Many of
the tone buildings, foundations, roads, and curbstones in Baltimore were
built of rock from both the Jones Falls and Gwynns Falls quarries. The
blue-gray color of fresh stone caused the term "blue stone" to
be used by the quarrymen. The last building stone quarry in Baltimore closed
in 1958.

Ellicott City "Granite"..... a porphyritic gneiss that was
first quarried in the late 18th century. It was used in building the Basilica
of the Assumption in Baltimore, which was erected during the period 1806
to 1821. Material was hauled from the Ellicott City area to Baltimore by
huge wagons drawn by nine yoke of oxen. After 1892, the stone was used
primarily in foundations and as paving stone. Little building stone was
produced from this area after 1896.

Woodstock Granite..... a pinkish-toned, coarse-grained, gray granitic
rock that was quarried near the town of Granite in Baltimore and Howard
counties. This rock was first quarried in 1832 and was used intermittently
until the 1920's. It was employed as a monument stone as well as being
used for building exteriors. Buildings made from this stone include: parts
of the Capitol building and the Library of Congress in Washington, D.C.,
the Baltimore Customs House, and the old Baltimore County Court House.
Many curbstones, paving blocks and bridges are made of this stone.

Cockeysville Marble... a white, crystalline, metalimestone, most famous
for its use in the Washington Monument in Washington, D.C. The first 152
feet of the monument, built between 1845 and 1854, were faced with Cockeysville
stone from a quarry near Texas, about 12 miles north of Baltimore. When
funds were depleted, work ceased for 25 years and was resumed again in
1879 using a marble from Lee, Massachusetts. Four courses of this stone
were used; however, it proved too costly and the remainder of the structure
was faced with marble from a quarry in the Cockeysville area. The marble
was also used in the construction of the Washington Monument in Baltimore
City. By the 1840's-1850's, the marble was very popular and readily available
for use in building the stone front steps of many of the older row houses
in Baltimore. The Beaver Dam quarry at Cockeysville furnished marble used
for the 108 columns in the wings of the National Capitol at Washington,
D.C. Today, quarries work the Cockeysville Marble primarily for crushed
stone and high-purity calcite.

Slate..... a bluish-gray, thin-bedded, fade resistant slate was quarried
from the Peach Bottom-Cardiff area in Harford County and, to a lesser extent,from
the Ijamsville area in Frederick County. The Peach Bottom area was worked
as early as 1750 for local use. The first commercial Peach Bottom quarry
opened in 1812, about the same time that work began in the Ijamsville area.
The Ijamsville slates did not achieve the popularity afforded those from
Peach Bottom because of their dullness and softness or lack of "ring," and
operations closed in 1892. Slate was quarried from Peach Bottom as late
as 1957 for granules in composition roofing shingles.

"Seneca Red" Sandstone..... a reddish to purplish brown, fine-grained,
arkosic sandstone or "Brownstone" was quarried extensively along
the Potomac River in Montgomery and Frederick Counties. This Triassic stone
was initially used for the "Potowmack Canal" built around
1774 and again for the C & O Canal in the early 1830's. It became a
popular building stone during the period between 1840 and 1889. Many buildings
in Washington, D.C., and in Baltimore were constructed of brownstone. In
1847, it was used to build the Smithsonian Institution Building in Washington,
D.C. The stone is readily carved and chiseled when first quarried but later
hardens on exposure to air. There is a tendency of the rock to spall if
laid "on edge," therefore, careful placement was required.

"Potomac Marble"..... also known as "calico rock" or "Potomac
Breccia," is a multi-colored conglomerate of Triassic age and
is composed of rounded quartz and limestone pebbles cemented in a calcareous
matrix. Benjamin Latrobe first reported finding this rock in 1815. This
stone, probably quarried from Montgomery County, was used for the twenty-foot
columns in the old U.S. House of Representatives (now Statuary Hall). It
proved to be difficult to work because of the differing hardness of the
pebbles and matrix and thus never attained widespread use. The stone was
quarried primarily in Frederick County, most extensively along the Potomac
River, near Washington Junction. One company intermittently worked this
stone as late as 1898.

Wakefield Marble..... a variegated marble used for altar fronts and interior
decorations was quarried in Carroll and Frederick Counties. The colors
range from "deep red," "salmon," "lavender veined," "undulated
pink and white," "ruby" to black to white. The marble's
variety of color was its drawback, as it was neither consistent nor predictable.
The marble was worked around the turn of the 20th century.

Serpentinite..... a patterned rock occurring in various shades of green
from pale leek to greenish black that has been used both as a building
stone and as a sawed and polished ornamental stone. Serpentinite from Baltimore
County was used to build the Mount Vernon Place Methodist Church in Baltimore
City. Cut and polished, it is also known as "Maryland Green Marble" or "verde
antique." It was extensively quarried near Cambria and Broad Creek
in Harford County as early as 1870. Stone from Broad Creek was shipped
to New York and was used in the Empire State Building in New York City.
This stone was also crushed for use in terrazzo flooring in the early 1970's.
A recent attempt to reopen the quarry in Cambria failed.

Sykesville Gneiss..... a dark gray, often schistose gneiss with a roughly
rectangular fracture pattern is currently being quarried near Potomac in
Montgomery County and was at one time used extensively in the Washington,
D.C. area for foundation and rubble stone. The stone was first worked commercially
as "granite" about 1850. The early settlers in the Washington
area used many of the schists and gneisses found along the PotomacRiver.
This Sykesville stone may be what was once known as "Potomac Bluestone."

Setters Quartzite..... a thinly layered tan quartzite that has been used
for many years as a flagstone and as building material. Tourmaline crystals
are often present on cleavage surfaces. The stone has become popular in
recent years for use in many of the houses and buildings in Towson and
Baltimore. It is currently being quarried near Marriottsville in both Howard
and Baltimore Counties.

Paleozoic Sandstones..... four sandstone beds which range in age from
Silurian to Mississippian have been quarried in Western Maryland for use
in that area. The Tuscarora sandstone has been used for foundation stones
and trim in many of the older buildings at Cumberland. The Oriskany, a
yellow to buff sandstone was also widely used there; however the stone
is soft and tends to disintegrate with time. Currently, both the Pocono,
a thin-bedded brown sandstone, and the Pottsville, a massive gray conglomeratic
sandstone, have limited use for flagstone, building facing, and rubble
stone.

Many other rock formations were used throughout Maryland for building material.
Often these were simply rocks picked up near the site of construction and are
termed "fieldstone." Initially, most building stone was obtained
this way, but about 1825 technology and transportation had developed to the
point that it was feasible to quarry stone at specific sites. In addition to
the better know quarries, many small quarries sprang up throughout Maryland
to satisfy the local demand. Even after the better building stones became everywhere
available, it often proved to be economic to use field stone and local quarry
rubble for hidden foundation work. Before the era of the massive stone buildings
abated, stone was imported from as far as Indiana. The Baltimore Museum of
Art, completed in 1929 was made from Indiana limestone.

The building stone industry of Maryland in recent years has diminished
in importance. New construction technology, together with a less labor-intensive
economy and modern architectural leanings have reduced the demand for stone.
Ample deposits of stone are still available, but present trends do not indicate
a revival of the building stone trade in the foreseeable future.

Downloads and Links

This publication is available as a pamphlet entitled "Building Stones of Maryland" from our Publications Office

This pamphlet was prepared by by Karen R. Kuff and James R. Brooks, 1990Compiled by the Maryland Geological Survey, 2300 St. Paul Street, Baltimore, MD 21218
This electronic version of "Building Stones of Maryland" was prepared by Bob Conkwright, Division of Coastal and Estuarine Geology, Maryland Geological Survey. Please send comments on this page to Dale Shelton (dshelton@mgs.md.gov)